Vitamin K, a fat soluble vitamin discovered in the 1930’s, is best known for its role in blood coagulation or blood clotting.  This form is also known as vitamin K1 or phylloquinone.  However there is another form of vitamin K that hasn’t received as much attention until the 21st century – vitamin K2.  Vitamin K2, also known as menaquinone, is made by our intestinal bacteria and also is found in certain food sources.  Deficiencies of vitamin K1 are rare but deficiencies of vitamin K2 are more common.  It is the vitamin K2 form that seems to have far-reaching roles that appear to make a meaningful difference in the health of our hearts, bones and of prostate cancer.